Dear you are having palpitations. Anemia when severe can cause what we call hyperdynamic circulation. Clinically an anemic person is pale. Hyperthyroidism can also cause it. Clinically a patient of hyperthyroidism has increased appetite yet a loss of body weight, irritability, decrease in sleep, tremors of hands, diarrhoea and sometimes bulging of eyes. Finally lesions of heart should be ruled out especially if you have a history of rheumatic fever. So you should have your Hemoglobin, Thyroid functions and EKG done. Thanks and take care.